This KB explores How To Install and Configure Zabbix on Ubuntu 18.04
Navigate to https://repo.zabbix.com/zabbix/
Find the release from the current version.
wget https://repo.zabbix.com/zabbix/4.1/ubuntu/pool/main/z/zabbix/zabbix-agent_4.2.0~alpha1-1%2Bbionic_amd64.deb |
# dpkg -i zabbix-agent_4.2.0~alpha1-1+bionic_amd64.deb |
apt update |
# service zabbix-agent start |